* Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997

/*
* Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Extensively modified by Motonori Shindo ([email protected]) for more
* complete PPP support.
*/

/* \summary: Point to Point Protocol (PPP) printer */

/*
* TODO:
* o resolve XXX as much as possible
* o MP support
* o BAP support
*/

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: print-ppp.c,v 1.11 2024/09/02 16:15:32 christos Exp $");
#endif

#include <config.h>

#include "netdissect-stdinc.h"

#include <stdlib.h>

#ifdef __bsdi__
#include <net/slcompress.h>
#include <net/if_ppp.h>
#endif

#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"
#include "ppp.h"
#include "chdlc.h"
#include "ethertype.h"
#include "oui.h"
#include "netdissect-alloc.h"

/*
* The following constants are defined by IANA. Please refer to
* https://www.isi.edu/in-notes/iana/assignments/ppp-numbers
* for the up-to-date information.
*/

/* Protocol Codes defined in ppp.h */

static const struct tok ppptype2str[] = {
{ PPP_IP, "IP" },
{ PPP_OSI, "OSI" },
{ PPP_NS, "NS" },
{ PPP_DECNET, "DECNET" },
{ PPP_APPLE, "APPLE" },
{ PPP_IPX, "IPX" },
{ PPP_VJC, "VJC IP" },
{ PPP_VJNC, "VJNC IP" },
{ PPP_BRPDU, "BRPDU" },
{ PPP_STII, "STII" },
{ PPP_VINES, "VINES" },
{ PPP_MPLS_UCAST, "MPLS" },
{ PPP_MPLS_MCAST, "MPLS" },
{ PPP_COMP, "Compressed"},
{ PPP_ML, "MLPPP"},
{ PPP_IPV6, "IP6"},

{ PPP_HELLO, "HELLO" },
{ PPP_LUXCOM, "LUXCOM" },
{ PPP_SNS, "SNS" },
{ PPP_IPCP, "IPCP" },
{ PPP_OSICP, "OSICP" },
{ PPP_NSCP, "NSCP" },
{ PPP_DECNETCP, "DECNETCP" },
{ PPP_APPLECP, "APPLECP" },
{ PPP_IPXCP, "IPXCP" },
{ PPP_STIICP, "STIICP" },
{ PPP_VINESCP, "VINESCP" },
{ PPP_IPV6CP, "IP6CP" },
{ PPP_MPLSCP, "MPLSCP" },

{ PPP_LCP, "LCP" },
{ PPP_PAP, "PAP" },
{ PPP_LQM, "LQM" },
{ PPP_CHAP, "CHAP" },
{ PPP_EAP, "EAP" },
{ PPP_SPAP, "SPAP" },
{ PPP_SPAP_OLD, "Old-SPAP" },
{ PPP_BACP, "BACP" },
{ PPP_BAP, "BAP" },
{ PPP_MPCP, "MLPPP-CP" },
{ PPP_CCP, "CCP" },
{ 0, NULL }
};

/* Control Protocols (LCP/IPCP/CCP etc.) Codes defined in RFC 1661 */

#define CPCODES_VEXT 0 /* Vendor-Specific (RFC2153) */
#define CPCODES_CONF_REQ 1 /* Configure-Request */
#define CPCODES_CONF_ACK 2 /* Configure-Ack */
#define CPCODES_CONF_NAK 3 /* Configure-Nak */
#define CPCODES_CONF_REJ 4 /* Configure-Reject */
#define CPCODES_TERM_REQ 5 /* Terminate-Request */
#define CPCODES_TERM_ACK 6 /* Terminate-Ack */
#define CPCODES_CODE_REJ 7 /* Code-Reject */
#define CPCODES_PROT_REJ 8 /* Protocol-Reject (LCP only) */
#define CPCODES_ECHO_REQ 9 /* Echo-Request (LCP only) */
#define CPCODES_ECHO_RPL 10 /* Echo-Reply (LCP only) */
#define CPCODES_DISC_REQ 11 /* Discard-Request (LCP only) */
#define CPCODES_ID 12 /* Identification (LCP only) RFC1570 */
#define CPCODES_TIME_REM 13 /* Time-Remaining (LCP only) RFC1570 */
#define CPCODES_RESET_REQ 14 /* Reset-Request (CCP only) RFC1962 */
#define CPCODES_RESET_REP 15 /* Reset-Reply (CCP only) */

static const struct tok cpcodes[] = {
{CPCODES_VEXT, "Vendor-Extension"}, /* RFC2153 */
{CPCODES_CONF_REQ, "Conf-Request"},
{CPCODES_CONF_ACK, "Conf-Ack"},
{CPCODES_CONF_NAK, "Conf-Nack"},
{CPCODES_CONF_REJ, "Conf-Reject"},
{CPCODES_TERM_REQ, "Term-Request"},
{CPCODES_TERM_ACK, "Term-Ack"},
{CPCODES_CODE_REJ, "Code-Reject"},
{CPCODES_PROT_REJ, "Prot-Reject"},
{CPCODES_ECHO_REQ, "Echo-Request"},
{CPCODES_ECHO_RPL, "Echo-Reply"},
{CPCODES_DISC_REQ, "Disc-Req"},
{CPCODES_ID, "Ident"}, /* RFC1570 */
{CPCODES_TIME_REM, "Time-Rem"}, /* RFC1570 */
{CPCODES_RESET_REQ, "Reset-Req"}, /* RFC1962 */
{CPCODES_RESET_REP, "Reset-Ack"}, /* RFC1962 */
{0, NULL}
};

/* LCP Config Options */

#define LCPOPT_VEXT 0
#define LCPOPT_MRU 1
#define LCPOPT_ACCM 2
#define LCPOPT_AP 3
#define LCPOPT_QP 4
#define LCPOPT_MN 5
#define LCPOPT_DEP6 6
#define LCPOPT_PFC 7
#define LCPOPT_ACFC 8
#define LCPOPT_FCSALT 9
#define LCPOPT_SDP 10
#define LCPOPT_NUMMODE 11
#define LCPOPT_DEP12 12
#define LCPOPT_CBACK 13
#define LCPOPT_DEP14 14
#define LCPOPT_DEP15 15
#define LCPOPT_DEP16 16
#define LCPOPT_MLMRRU 17
#define LCPOPT_MLSSNHF 18
#define LCPOPT_MLED 19
#define LCPOPT_PROP 20
#define LCPOPT_DCEID 21
#define LCPOPT_MPP 22
#define LCPOPT_LD 23
#define LCPOPT_LCPAOPT 24
#define LCPOPT_COBS 25
#define LCPOPT_PE 26
#define LCPOPT_MLHF 27
#define LCPOPT_I18N 28
#define LCPOPT_SDLOS 29
#define LCPOPT_PPPMUX 30

static const char *lcpconfopts[] = {
"Vend-Ext", /* (0) */
"MRU", /* (1) */
"ACCM", /* (2) */
"Auth-Prot", /* (3) */
"Qual-Prot", /* (4) */
"Magic-Num", /* (5) */
"deprecated(6)", /* used to be a Quality Protocol */
"PFC", /* (7) */
"ACFC", /* (8) */
"FCS-Alt", /* (9) */
"SDP", /* (10) */
"Num-Mode", /* (11) */
"deprecated(12)", /* used to be a Multi-Link-Procedure*/
"Call-Back", /* (13) */
"deprecated(14)", /* used to be a Connect-Time */
"deprecated(15)", /* used to be a Compound-Frames */
"deprecated(16)", /* used to be a Nominal-Data-Encap */
"MRRU", /* (17) */
"12-Bit seq #", /* (18) */
"End-Disc", /* (19) */
"Proprietary", /* (20) */
"DCE-Id", /* (21) */
"MP+", /* (22) */
"Link-Disc", /* (23) */
"LCP-Auth-Opt", /* (24) */
"COBS", /* (25) */
"Prefix-elision", /* (26) */
"Multilink-header-Form",/* (27) */
"I18N", /* (28) */
"SDL-over-SONET/SDH", /* (29) */
"PPP-Muxing", /* (30) */
};

#define NUM_LCPOPTS (sizeof(lcpconfopts) / sizeof(lcpconfopts[0]))

/* ECP - to be supported */

/* CCP Config Options */

#define CCPOPT_OUI 0 /* RFC1962 */
#define CCPOPT_PRED1 1 /* RFC1962 */
#define CCPOPT_PRED2 2 /* RFC1962 */
#define CCPOPT_PJUMP 3 /* RFC1962 */
/* 4-15 unassigned */
#define CCPOPT_HPPPC 16 /* RFC1962 */
#define CCPOPT_STACLZS 17 /* RFC1974 */
#define CCPOPT_MPPC 18 /* RFC2118 */
#define CCPOPT_GFZA 19 /* RFC1962 */
#define CCPOPT_V42BIS 20 /* RFC1962 */
#define CCPOPT_BSDCOMP 21 /* RFC1977 */
/* 22 unassigned */
#define CCPOPT_LZSDCP 23 /* RFC1967 */
#define CCPOPT_MVRCA 24 /* RFC1975 */
#define CCPOPT_DEC 25 /* RFC1976 */
#define CCPOPT_DEFLATE 26 /* RFC1979 */
/* 27-254 unassigned */
#define CCPOPT_RESV 255 /* RFC1962 */

static const struct tok ccpconfopts_values[] = {
{ CCPOPT_OUI, "OUI" },
{ CCPOPT_PRED1, "Pred-1" },
{ CCPOPT_PRED2, "Pred-2" },
{ CCPOPT_PJUMP, "Puddle" },
{ CCPOPT_HPPPC, "HP-PPC" },
{ CCPOPT_STACLZS, "Stac-LZS" },
{ CCPOPT_MPPC, "MPPC" },
{ CCPOPT_GFZA, "Gand-FZA" },
{ CCPOPT_V42BIS, "V.42bis" },
{ CCPOPT_BSDCOMP, "BSD-Comp" },
{ CCPOPT_LZSDCP, "LZS-DCP" },
{ CCPOPT_MVRCA, "MVRCA" },
{ CCPOPT_DEC, "DEC" },
{ CCPOPT_DEFLATE, "Deflate" },
{ CCPOPT_RESV, "Reserved"},
{0, NULL}
};

/* BACP Config Options */

#define BACPOPT_FPEER 1 /* RFC2125 */

static const struct tok bacconfopts_values[] = {
{ BACPOPT_FPEER, "Favored-Peer" },
{0, NULL}
};

/* SDCP - to be supported */

/* IPCP Config Options */
#define IPCPOPT_2ADDR 1 /* RFC1172, RFC1332 (deprecated) */
#define IPCPOPT_IPCOMP 2 /* RFC1332 */
#define IPCPOPT_ADDR 3 /* RFC1332 */
#define IPCPOPT_MOBILE4 4 /* RFC2290 */
#define IPCPOPT_PRIDNS 129 /* RFC1877 */
#define IPCPOPT_PRINBNS 130 /* RFC1877 */
#define IPCPOPT_SECDNS 131 /* RFC1877 */
#define IPCPOPT_SECNBNS 132 /* RFC1877 */

static const struct tok ipcpopt_values[] = {
{ IPCPOPT_2ADDR, "IP-Addrs" },
{ IPCPOPT_IPCOMP, "IP-Comp" },
{ IPCPOPT_ADDR, "IP-Addr" },
{ IPCPOPT_MOBILE4, "Home-Addr" },
{ IPCPOPT_PRIDNS, "Pri-DNS" },
{ IPCPOPT_PRINBNS, "Pri-NBNS" },
{ IPCPOPT_SECDNS, "Sec-DNS" },
{ IPCPOPT_SECNBNS, "Sec-NBNS" },
{ 0, NULL }
};

#define IPCPOPT_IPCOMP_HDRCOMP 0x61 /* rfc3544 */
#define IPCPOPT_IPCOMP_MINLEN 14

static const struct tok ipcpopt_compproto_values[] = {
{ PPP_VJC, "VJ-Comp" },
{ IPCPOPT_IPCOMP_HDRCOMP, "IP Header Compression" },
{ 0, NULL }
};

static const struct tok ipcpopt_compproto_subopt_values[] = {
{ 1, "RTP-Compression" },
{ 2, "Enhanced RTP-Compression" },
{ 0, NULL }
};

/* IP6CP Config Options */
#define IP6CP_IFID 1

static const struct tok ip6cpopt_values[] = {
{ IP6CP_IFID, "Interface-ID" },
{ 0, NULL }
};

/* ATCP - to be supported */
/* OSINLCP - to be supported */
/* BVCP - to be supported */
/* BCP - to be supported */
/* IPXCP - to be supported */
/* MPLSCP - to be supported */

/* Auth Algorithms */

/* 0-4 Reserved (RFC1994) */
#define AUTHALG_CHAPMD5 5 /* RFC1994 */
#define AUTHALG_MSCHAP1 128 /* RFC2433 */
#define AUTHALG_MSCHAP2 129 /* RFC2795 */

static const struct tok authalg_values[] = {
{ AUTHALG_CHAPMD5, "MD5" },
{ AUTHALG_MSCHAP1, "MS-CHAPv1" },
{ AUTHALG_MSCHAP2, "MS-CHAPv2" },
{ 0, NULL }
};

/* FCS Alternatives - to be supported */

/* Multilink Endpoint Discriminator (RFC1717) */
#define MEDCLASS_NULL 0 /* Null Class */
#define MEDCLASS_LOCAL 1 /* Locally Assigned */
#define MEDCLASS_IPV4 2 /* Internet Protocol (IPv4) */
#define MEDCLASS_MAC 3 /* IEEE 802.1 global MAC address */
#define MEDCLASS_MNB 4 /* PPP Magic Number Block */
#define MEDCLASS_PSNDN 5 /* Public Switched Network Director Number */

/* PPP LCP Callback */
#define CALLBACK_AUTH 0 /* Location determined by user auth */
#define CALLBACK_DSTR 1 /* Dialing string */
#define CALLBACK_LID 2 /* Location identifier */
#define CALLBACK_E164 3 /* E.164 number */
#define CALLBACK_X500 4 /* X.500 distinguished name */
#define CALLBACK_CBCP 6 /* Location is determined during CBCP nego */

static const struct tok ppp_callback_values[] = {
{ CALLBACK_AUTH, "UserAuth" },
{ CALLBACK_DSTR, "DialString" },
{ CALLBACK_LID, "LocalID" },
{ CALLBACK_E164, "E.164" },
{ CALLBACK_X500, "X.500" },
{ CALLBACK_CBCP, "CBCP" },
{ 0, NULL }
};

/* CHAP */

#define CHAP_CHAL 1
#define CHAP_RESP 2
#define CHAP_SUCC 3
#define CHAP_FAIL 4

static const struct tok chapcode_values[] = {
{ CHAP_CHAL, "Challenge" },
{ CHAP_RESP, "Response" },
{ CHAP_SUCC, "Success" },
{ CHAP_FAIL, "Fail" },
{ 0, NULL}
};

/* PAP */

#define PAP_AREQ 1
#define PAP_AACK 2
#define PAP_ANAK 3

static const struct tok papcode_values[] = {
{ PAP_AREQ, "Auth-Req" },
{ PAP_AACK, "Auth-ACK" },
{ PAP_ANAK, "Auth-NACK" },
{ 0, NULL }
};

/* BAP */
#define BAP_CALLREQ 1
#define BAP_CALLRES 2
#define BAP_CBREQ 3
#define BAP_CBRES 4
#define BAP_LDQREQ 5
#define BAP_LDQRES 6
#define BAP_CSIND 7
#define BAP_CSRES 8

static u_int print_lcp_config_options(netdissect_options *, const u_char *p, u_int);
static u_int print_ipcp_config_options(netdissect_options *, const u_char *p, u_int);
static u_int print_ip6cp_config_options(netdissect_options *, const u_char *p, u_int);
static u_int print_ccp_config_options(netdissect_options *, const u_char *p, u_int);
static u_int print_bacp_config_options(netdissect_options *, const u_char *p, u_int);
static void handle_ppp(netdissect_options *, u_int proto, const u_char *p, u_int length);

/* generic Control Protocol (e.g. LCP, IPCP, CCP, etc.) handler */
static void
handle_ctrl_proto(netdissect_options *ndo,
u_int proto, const u_char *pptr, u_int length)
{
const char *typestr;
u_int code, len;
u_int (*pfunc)(netdissect_options *, const u_char *, u_int);
u_int tlen, advance;
const u_char *tptr;

tptr=pptr;

typestr = tok2str(ppptype2str, "unknown ctrl-proto (0x%04x)", proto);
ND_PRINT("%s, ", typestr);

if (length < 4) /* FIXME weak boundary checking */
goto trunc;
ND_TCHECK_2(tptr);

code = GET_U_1(tptr);
tptr++;

ND_PRINT("%s (0x%02x), id %u, length %u",
tok2str(cpcodes, "Unknown Opcode",code),
code,
GET_U_1(tptr), /* ID */
length + 2);
tptr++;

if (!ndo->ndo_vflag)
return;

len = GET_BE_U_2(tptr);
tptr += 2;

if (len < 4) {
ND_PRINT("\n\tencoded length %u (< 4))", len);
return;
}

if (len > length) {
ND_PRINT("\n\tencoded length %u (> packet length %u))", len, length);
return;
}
length = len;

ND_PRINT("\n\tencoded length %u (=Option(s) length %u)", len, len - 4);

if (length == 4)
return; /* there may be a NULL confreq etc. */

if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, pptr - 2, "\n\t", 6);

switch (code) {
case CPCODES_VEXT:
if (length < 11)
break;
ND_PRINT("\n\t Magic-Num 0x%08x", GET_BE_U_4(tptr));
tptr += 4;
ND_PRINT(" Vendor: %s (%u)",
tok2str(oui_values,"Unknown",GET_BE_U_3(tptr)),
GET_BE_U_3(tptr));
/* XXX: need to decode Kind and Value(s)? */
break;
case CPCODES_CONF_REQ:
case CPCODES_CONF_ACK:
case CPCODES_CONF_NAK:
case CPCODES_CONF_REJ:
tlen = len - 4; /* Code(1), Identifier(1) and Length(2) */
do {
switch (proto) {
case PPP_LCP:
pfunc = print_lcp_config_options;
break;
case PPP_IPCP:
pfunc = print_ipcp_config_options;
break;
case PPP_IPV6CP:
pfunc = print_ip6cp_config_options;
break;
case PPP_CCP:
pfunc = print_ccp_config_options;
break;
case PPP_BACP:
pfunc = print_bacp_config_options;
break;
default:
/*
* No print routine for the options for
* this protocol.
*/
pfunc = NULL;
break;
}

if (pfunc == NULL) /* catch the above null pointer if unknown CP */
break;

if ((advance = (*pfunc)(ndo, tptr, len)) == 0)
break;
if (tlen < advance) {
ND_PRINT(" [remaining options length %u < %u]",
tlen, advance);
nd_print_invalid(ndo);
break;
}
tlen -= advance;
tptr += advance;
} while (tlen != 0);
break;

case CPCODES_TERM_REQ:
case CPCODES_TERM_ACK:
/* XXX: need to decode Data? */
break;
case CPCODES_CODE_REJ:
/* XXX: need to decode Rejected-Packet? */
break;
case CPCODES_PROT_REJ:
if (length < 6)
break;
ND_PRINT("\n\t Rejected %s Protocol (0x%04x)",
tok2str(ppptype2str,"unknown", GET_BE_U_2(tptr)),
GET_BE_U_2(tptr));
/* XXX: need to decode Rejected-Information? - hexdump for now */
if (len > 6) {
ND_PRINT("\n\t Rejected Packet");
print_unknown_data(ndo, tptr + 2, "\n\t ", len - 2);
}
break;
case CPCODES_ECHO_REQ:
case CPCODES_ECHO_RPL:
case CPCODES_DISC_REQ:
if (length < 8)
break;
ND_PRINT("\n\t Magic-Num 0x%08x", GET_BE_U_4(tptr));
/* XXX: need to decode Data? - hexdump for now */
if (len > 8) {
ND_PRINT("\n\t -----trailing data-----");
ND_TCHECK_LEN(tptr + 4, len - 8);
print_unknown_data(ndo, tptr + 4, "\n\t ", len - 8);
}
break;
case CPCODES_ID:
if (length < 8)
break;
ND_PRINT("\n\t Magic-Num 0x%08x", GET_BE_U_4(tptr));
/* RFC 1661 says this is intended to be human readable */
if (len > 8) {
ND_PRINT("\n\t Message\n\t ");
if (nd_printn(ndo, tptr + 4, len - 4, ndo->ndo_snapend))
goto trunc;
}
break;
case CPCODES_TIME_REM:
if (length < 12)
break;
ND_PRINT("\n\t Magic-Num 0x%08x", GET_BE_U_4(tptr));
ND_PRINT(", Seconds-Remaining %us", GET_BE_U_4(tptr + 4));
/* XXX: need to decode Message? */
break;
default:
/* XXX this is dirty but we do not get the
* original pointer passed to the begin
* the PPP packet */
if (ndo->ndo_vflag <= 1)
print_unknown_data(ndo, pptr - 2, "\n\t ", length + 2);
break;
}
return;

trunc:
ND_PRINT("[|%s]", typestr);
}

/* LCP config options */
static u_int
print_lcp_config_options(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int opt, len;

if (length < 2)
return 0;
ND_TCHECK_2(p);
opt = GET_U_1(p);
len = GET_U_1(p + 1);
if (length < len)
return 0;
if (len < 2) {
if (opt < NUM_LCPOPTS)
ND_PRINT("\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
lcpconfopts[opt], opt, len);
else
ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
return 0;
}
if (opt < NUM_LCPOPTS)
ND_PRINT("\n\t %s Option (0x%02x), length %u", lcpconfopts[opt], opt, len);
else {
ND_PRINT("\n\tunknown LCP option 0x%02x", opt);
return len;
}

switch (opt) {
case LCPOPT_VEXT:
if (len < 6) {
ND_PRINT(" (length bogus, should be >= 6)");
return len;
}
ND_PRINT(": Vendor: %s (%u)",
tok2str(oui_values,"Unknown",GET_BE_U_3(p + 2)),
GET_BE_U_3(p + 2));
#if 0
ND_PRINT(", kind: 0x%02x", GET_U_1(p + 5));
ND_PRINT(", Value: 0x");
for (i = 0; i < len - 6; i++) {
ND_PRINT("%02x", GET_U_1(p + 6 + i));
}
#endif
break;
case LCPOPT_MRU:
if (len != 4) {
ND_PRINT(" (length bogus, should be = 4)");
return len;
}
ND_PRINT(": %u", GET_BE_U_2(p + 2));
break;
case LCPOPT_ACCM:
if (len != 6) {
ND_PRINT(" (length bogus, should be = 6)");
return len;
}
ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
break;
case LCPOPT_AP:
if (len < 4) {
ND_PRINT(" (length bogus, should be >= 4)");
return len;
}
ND_PRINT(": %s",
tok2str(ppptype2str, "Unknown Auth Proto (0x04x)", GET_BE_U_2(p + 2)));

switch (GET_BE_U_2(p + 2)) {
case PPP_CHAP:
ND_PRINT(", %s",
tok2str(authalg_values, "Unknown Auth Alg %u", GET_U_1(p + 4)));
break;
case PPP_PAP: /* fall through */
case PPP_EAP:
case PPP_SPAP:
case PPP_SPAP_OLD:
break;
default:
print_unknown_data(ndo, p, "\n\t", len);
}
break;
case LCPOPT_QP:
if (len < 4) {
ND_PRINT(" (length bogus, should be >= 4)");
return 0;
}
if (GET_BE_U_2(p + 2) == PPP_LQM)
ND_PRINT(": LQR");
else
ND_PRINT(": unknown");
break;
case LCPOPT_MN:
if (len != 6) {
ND_PRINT(" (length bogus, should be = 6)");
return 0;
}
ND_PRINT(": 0x%08x", GET_BE_U_4(p + 2));
break;
case LCPOPT_PFC:
break;
case LCPOPT_ACFC:
break;
case LCPOPT_LD:
if (len != 4) {
ND_PRINT(" (length bogus, should be = 4)");
return 0;
}
ND_PRINT(": 0x%04x", GET_BE_U_2(p + 2));
break;
case LCPOPT_CBACK:
if (len < 3) {
ND_PRINT(" (length bogus, should be >= 3)");
return 0;
}
ND_PRINT(": Callback Operation %s (%u)",
tok2str(ppp_callback_values, "Unknown", GET_U_1(p + 2)),
GET_U_1(p + 2));
break;
case LCPOPT_MLMRRU:
if (len != 4) {
ND_PRINT(" (length bogus, should be = 4)");
return 0;
}
ND_PRINT(": %u", GET_BE_U_2(p + 2));
break;
case LCPOPT_MLED:
if (len < 3) {
ND_PRINT(" (length bogus, should be >= 3)");
return 0;
}
switch (GET_U_1(p + 2)) { /* class */
case MEDCLASS_NULL:
ND_PRINT(": Null");
break;
case MEDCLASS_LOCAL:
ND_PRINT(": Local"); /* XXX */
break;
case MEDCLASS_IPV4:
if (len != 7) {
ND_PRINT(" (length bogus, should be = 7)");
return 0;
}
ND_PRINT(": IPv4 %s", GET_IPADDR_STRING(p + 3));
break;
case MEDCLASS_MAC:
if (len != 9) {
ND_PRINT(" (length bogus, should be = 9)");
return 0;
}
ND_PRINT(": MAC %s", GET_ETHERADDR_STRING(p + 3));
break;
case MEDCLASS_MNB:
ND_PRINT(": Magic-Num-Block"); /* XXX */
break;
case MEDCLASS_PSNDN:
ND_PRINT(": PSNDN"); /* XXX */
break;
default:
ND_PRINT(": Unknown class %u", GET_U_1(p + 2));
break;
}
break;

/* XXX: to be supported */
#if 0
case LCPOPT_DEP6:
case LCPOPT_FCSALT:
case LCPOPT_SDP:
case LCPOPT_NUMMODE:
case LCPOPT_DEP12:
case LCPOPT_DEP14:
case LCPOPT_DEP15:
case LCPOPT_DEP16:
case LCPOPT_MLSSNHF:
case LCPOPT_PROP:
case LCPOPT_DCEID:
case LCPOPT_MPP:
case LCPOPT_LCPAOPT:
case LCPOPT_COBS:
case LCPOPT_PE:
case LCPOPT_MLHF:
case LCPOPT_I18N:
case LCPOPT_SDLOS:
case LCPOPT_PPPMUX:
break;
#endif
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2);
break;
}

if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2); /* exclude TLV header */

return len;

trunc:
ND_PRINT("[|lcp]");
return 0;
}

/* ML-PPP*/
static const struct tok ppp_ml_flag_values[] = {
{ 0x80, "begin" },
{ 0x40, "end" },
{ 0, NULL }
};

static void
handle_mlppp(netdissect_options *ndo,
const u_char *p, u_int length)
{
if (!ndo->ndo_eflag)
ND_PRINT("MLPPP, ");

if (length < 2) {
ND_PRINT("[|mlppp]");
return;
}
if (!ND_TTEST_2(p)) {
ND_PRINT("[|mlppp]");
return;
}

ND_PRINT("seq 0x%03x, Flags [%s], length %u",
(GET_BE_U_2(p))&0x0fff,
/* only support 12-Bit sequence space for now */
bittok2str(ppp_ml_flag_values, "none", GET_U_1(p) & 0xc0),
length);
}

/* CHAP */
static void
handle_chap(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int code, len;
u_int val_size, name_size, msg_size;
const u_char *p0;
u_int i;

p0 = p;
if (length < 1) {
ND_PRINT("[|chap]");
return;
} else if (length < 4) {
ND_PRINT("[|chap 0x%02x]", GET_U_1(p));
return;
}

code = GET_U_1(p);
ND_PRINT("CHAP, %s (0x%02x)",
tok2str(chapcode_values,"unknown",code),
code);
p++;

ND_PRINT(", id %u", GET_U_1(p)); /* ID */
p++;

len = GET_BE_U_2(p);
p += 2;

/*
* Note that this is a generic CHAP decoding routine. Since we
* don't know which flavor of CHAP (i.e. CHAP-MD5, MS-CHAPv1,
* MS-CHAPv2) is used at this point, we can't decode packet
* specifically to each algorithms. Instead, we simply decode
* the GCD (Greatest Common Denominator) for all algorithms.
*/
switch (code) {
case CHAP_CHAL:
case CHAP_RESP:
if (length - (p - p0) < 1)
return;
val_size = GET_U_1(p); /* value size */
p++;
if (length - (p - p0) < val_size)
return;
ND_PRINT(", Value ");
for (i = 0; i < val_size; i++) {
ND_PRINT("%02x", GET_U_1(p));
p++;
}
name_size = len - (u_int)(p - p0);
ND_PRINT(", Name ");
for (i = 0; i < name_size; i++) {
fn_print_char(ndo, GET_U_1(p));
p++;
}
break;
case CHAP_SUCC:
case CHAP_FAIL:
msg_size = len - (u_int)(p - p0);
ND_PRINT(", Msg ");
for (i = 0; i< msg_size; i++) {
fn_print_char(ndo, GET_U_1(p));
p++;
}
break;
}
}

/* PAP (see RFC 1334) */
static void
handle_pap(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int code, len;
u_int peerid_len, passwd_len, msg_len;
const u_char *p0;
u_int i;

p0 = p;
if (length < 1) {
ND_PRINT("[|pap]");
return;
} else if (length < 4) {
ND_PRINT("[|pap 0x%02x]", GET_U_1(p));
return;
}

code = GET_U_1(p);
ND_PRINT("PAP, %s (0x%02x)",
tok2str(papcode_values, "unknown", code),
code);
p++;

ND_PRINT(", id %u", GET_U_1(p)); /* ID */
p++;

len = GET_BE_U_2(p);
p += 2;

if (len > length) {
ND_PRINT(", length %u > packet size", len);
return;
}
length = len;
if (length < (size_t)(p - p0)) {
ND_PRINT(", length %u < PAP header length", length);
return;
}

switch (code) {
case PAP_AREQ:
/* A valid Authenticate-Request is 6 or more octets long. */
if (len < 6)
goto trunc;
if (length - (p - p0) < 1)
return;
peerid_len = GET_U_1(p); /* Peer-ID Length */
p++;
if (length - (p - p0) < peerid_len)
return;
ND_PRINT(", Peer ");
for (i = 0; i < peerid_len; i++) {
fn_print_char(ndo, GET_U_1(p));
p++;
}

if (length - (p - p0) < 1)
return;
passwd_len = GET_U_1(p); /* Password Length */
p++;
if (length - (p - p0) < passwd_len)
return;
ND_PRINT(", Name ");
for (i = 0; i < passwd_len; i++) {
fn_print_char(ndo, GET_U_1(p));
p++;
}
break;
case PAP_AACK:
case PAP_ANAK:
/* Although some implementations ignore truncation at
* this point and at least one generates a truncated
* packet, RFC 1334 section 2.2.2 clearly states that
* both AACK and ANAK are at least 5 bytes long.
*/
if (len < 5)
goto trunc;
if (length - (p - p0) < 1)
return;
msg_len = GET_U_1(p); /* Msg-Length */
p++;
if (length - (p - p0) < msg_len)
return;
ND_PRINT(", Msg ");
for (i = 0; i< msg_len; i++) {
fn_print_char(ndo, GET_U_1(p));
p++;
}
break;
}
return;

trunc:
ND_PRINT("[|pap]");
}

/* BAP */
static void
handle_bap(netdissect_options *ndo _U_,
const u_char *p _U_, u_int length _U_)
{
/* XXX: to be supported!! */
}

/* IPCP config options */
static u_int
print_ipcp_config_options(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int opt, len;
u_int compproto, ipcomp_subopttotallen, ipcomp_subopt, ipcomp_suboptlen;

if (length < 2)
return 0;
ND_TCHECK_2(p);
opt = GET_U_1(p);
len = GET_U_1(p + 1);
if (length < len)
return 0;
if (len < 2) {
ND_PRINT("\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ipcpopt_values,"unknown",opt),
opt,
len);
return 0;
}

ND_PRINT("\n\t %s Option (0x%02x), length %u",
tok2str(ipcpopt_values,"unknown",opt),
opt,
len);

switch (opt) {
case IPCPOPT_2ADDR: /* deprecated */
if (len != 10) {
ND_PRINT(" (length bogus, should be = 10)");
return len;
}
ND_PRINT(": src %s, dst %s",
GET_IPADDR_STRING(p + 2),
GET_IPADDR_STRING(p + 6));
break;
case IPCPOPT_IPCOMP:
if (len < 4) {
ND_PRINT(" (length bogus, should be >= 4)");
return 0;
}
compproto = GET_BE_U_2(p + 2);

ND_PRINT(": %s (0x%02x):",
tok2str(ipcpopt_compproto_values, "Unknown", compproto),
compproto);

switch (compproto) {
case PPP_VJC:
/* XXX: VJ-Comp parameters should be decoded */
break;
case IPCPOPT_IPCOMP_HDRCOMP:
if (len < IPCPOPT_IPCOMP_MINLEN) {
ND_PRINT(" (length bogus, should be >= %u)",
IPCPOPT_IPCOMP_MINLEN);
return 0;
}

ND_TCHECK_LEN(p + 2, IPCPOPT_IPCOMP_MINLEN);
ND_PRINT("\n\t TCP Space %u, non-TCP Space %u"
", maxPeriod %u, maxTime %u, maxHdr %u",
GET_BE_U_2(p + 4),
GET_BE_U_2(p + 6),
GET_BE_U_2(p + 8),
GET_BE_U_2(p + 10),
GET_BE_U_2(p + 12));

/* suboptions present ? */
if (len > IPCPOPT_IPCOMP_MINLEN) {
ipcomp_subopttotallen = len - IPCPOPT_IPCOMP_MINLEN;
p += IPCPOPT_IPCOMP_MINLEN;

ND_PRINT("\n\t Suboptions, length %u", ipcomp_subopttotallen);

while (ipcomp_subopttotallen >= 2) {
ND_TCHECK_2(p);
ipcomp_subopt = GET_U_1(p);
ipcomp_suboptlen = GET_U_1(p + 1);

/* sanity check */
if (ipcomp_subopt == 0 ||
ipcomp_suboptlen == 0 )
break;

/* XXX: just display the suboptions for now */
ND_PRINT("\n\t\t%s Suboption #%u, length %u",
tok2str(ipcpopt_compproto_subopt_values,
"Unknown",
ipcomp_subopt),
ipcomp_subopt,
ipcomp_suboptlen);
if (ipcomp_subopttotallen < ipcomp_suboptlen) {
ND_PRINT(" [remaining suboptions length %u < %u]",
ipcomp_subopttotallen, ipcomp_suboptlen);
nd_print_invalid(ndo);
break;
}
ipcomp_subopttotallen -= ipcomp_suboptlen;
p += ipcomp_suboptlen;
}
}
break;
default:
break;
}
break;

case IPCPOPT_ADDR: /* those options share the same format - fall through */
case IPCPOPT_MOBILE4:
case IPCPOPT_PRIDNS:
case IPCPOPT_PRINBNS:
case IPCPOPT_SECDNS:
case IPCPOPT_SECNBNS:
if (len != 6) {
ND_PRINT(" (length bogus, should be = 6)");
return 0;
}
ND_PRINT(": %s", GET_IPADDR_STRING(p + 2));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1 && ND_TTEST_LEN(p + 2, len - 2))
print_unknown_data(ndo, p + 2, "\n\t ", len - 2); /* exclude TLV header */
return len;

trunc:
ND_PRINT("[|ipcp]");
return 0;
}

/* IP6CP config options */
static u_int
print_ip6cp_config_options(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int opt, len;

if (length < 2)
return 0;
ND_TCHECK_2(p);
opt = GET_U_1(p);
len = GET_U_1(p + 1);
if (length < len)
return 0;
if (len < 2) {
ND_PRINT("\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ip6cpopt_values,"unknown",opt),
opt,
len);
return 0;
}

ND_PRINT("\n\t %s Option (0x%02x), length %u",
tok2str(ip6cpopt_values,"unknown",opt),
opt,
len);

switch (opt) {
case IP6CP_IFID:
if (len != 10) {
ND_PRINT(" (length bogus, should be = 10)");
return len;
}
ND_TCHECK_8(p + 2);
ND_PRINT(": %04x:%04x:%04x:%04x",
GET_BE_U_2(p + 2),
GET_BE_U_2(p + 4),
GET_BE_U_2(p + 6),
GET_BE_U_2(p + 8));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2); /* exclude TLV header */

return len;

trunc:
ND_PRINT("[|ip6cp]");
return 0;
}

/* CCP config options */
static u_int
print_ccp_config_options(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int opt, len;

if (length < 2)
return 0;
ND_TCHECK_2(p);
opt = GET_U_1(p);
len = GET_U_1(p + 1);
if (length < len)
return 0;
if (len < 2) {
ND_PRINT("\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(ccpconfopts_values, "Unknown", opt),
opt,
len);
return 0;
}

ND_PRINT("\n\t %s Option (0x%02x), length %u",
tok2str(ccpconfopts_values, "Unknown", opt),
opt,
len);

switch (opt) {
case CCPOPT_BSDCOMP:
if (len < 3) {
ND_PRINT(" (length bogus, should be >= 3)");
return len;
}
ND_PRINT(": Version: %u, Dictionary Bits: %u",
GET_U_1(p + 2) >> 5,
GET_U_1(p + 2) & 0x1f);
break;
case CCPOPT_MVRCA:
if (len < 4) {
ND_PRINT(" (length bogus, should be >= 4)");
return len;
}
ND_PRINT(": Features: %u, PxP: %s, History: %u, #CTX-ID: %u",
(GET_U_1(p + 2) & 0xc0) >> 6,
(GET_U_1(p + 2) & 0x20) ? "Enabled" : "Disabled",
GET_U_1(p + 2) & 0x1f,
GET_U_1(p + 3));
break;
case CCPOPT_DEFLATE:
if (len < 4) {
ND_PRINT(" (length bogus, should be >= 4)");
return len;
}
ND_PRINT(": Window: %uK, Method: %s (0x%x), MBZ: %u, CHK: %u",
(GET_U_1(p + 2) & 0xf0) >> 4,
((GET_U_1(p + 2) & 0x0f) == 8) ? "zlib" : "unknown",
GET_U_1(p + 2) & 0x0f,
(GET_U_1(p + 3) & 0xfc) >> 2,
GET_U_1(p + 3) & 0x03);
break;

/* XXX: to be supported */
#if 0
case CCPOPT_OUI:
case CCPOPT_PRED1:
case CCPOPT_PRED2:
case CCPOPT_PJUMP:
case CCPOPT_HPPPC:
case CCPOPT_STACLZS:
case CCPOPT_MPPC:
case CCPOPT_GFZA:
case CCPOPT_V42BIS:
case CCPOPT_LZSDCP:
case CCPOPT_DEC:
case CCPOPT_RESV:
break;
#endif
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2); /* exclude TLV header */

return len;

trunc:
ND_PRINT("[|ccp]");
return 0;
}

/* BACP config options */
static u_int
print_bacp_config_options(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int opt, len;

if (length < 2)
return 0;
ND_TCHECK_2(p);
opt = GET_U_1(p);
len = GET_U_1(p + 1);
if (length < len)
return 0;
if (len < 2) {
ND_PRINT("\n\t %s Option (0x%02x), length %u (length bogus, should be >= 2)",
tok2str(bacconfopts_values, "Unknown", opt),
opt,
len);
return 0;
}

ND_PRINT("\n\t %s Option (0x%02x), length %u",
tok2str(bacconfopts_values, "Unknown", opt),
opt,
len);

switch (opt) {
case BACPOPT_FPEER:
if (len != 6) {
ND_PRINT(" (length bogus, should be = 6)");
return len;
}
ND_PRINT(": Magic-Num 0x%08x", GET_BE_U_4(p + 2));
break;
default:
/*
* Unknown option; dump it as raw bytes now if we're
* not going to do so below.
*/
if (ndo->ndo_vflag < 2)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2);
break;
}
if (ndo->ndo_vflag > 1)
print_unknown_data(ndo, p + 2, "\n\t ", len - 2); /* exclude TLV header */

return len;

trunc:
ND_PRINT("[|bacp]");
return 0;
}

/*
* Un-escape RFC 1662 PPP in HDLC-like framing, with octet escapes.
* The length argument is the on-the-wire length, not the captured
* length; we can only un-escape the captured part.
*/
static void
ppp_hdlc(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int caplen = ND_BYTES_AVAILABLE_AFTER(p);
u_char *b, *t, c;
const u_char *s;
u_int i, proto;

if (caplen == 0)
return;

if (length == 0)
return;

b = (u_char *)malloc(caplen);
if (b == NULL) {
(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
"%s: malloc", __func__);
}

/*
* Unescape all the data into a temporary, private, buffer.
* Do this so that we don't overwrite the original packet
* contents.
*/
for (s = p, t = b, i = caplen; i != 0; i--) {
c = GET_U_1(s);
s++;
if (c == 0x7d) {
if (i <= 1)
break;
i--;
c = GET_U_1(s) ^ 0x20;
s++;
}
*t++ = c;
}

/*
* Switch to the output buffer for dissection, and save it
* on the buffer stack so it can be freed; our caller must
* pop it when done.
*/
if (!nd_push_buffer(ndo, b, b, (u_int)(t - b))) {
free(b);
(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
"%s: can't push buffer on buffer stack", __func__);
}
length = ND_BYTES_AVAILABLE_AFTER(b);

/* now lets guess about the payload codepoint format */
if (length < 1)
goto trunc;
proto = GET_U_1(b); /* start with a one-octet codepoint guess */

switch (proto) {
case PPP_IP:
ip_print(ndo, b + 1, length - 1);
goto cleanup;
case PPP_IPV6:
ip6_print(ndo, b + 1, length - 1);
goto cleanup;
default: /* no luck - try next guess */
break;
}

if (length < 2)
goto trunc;
proto = GET_BE_U_2(b); /* next guess - load two octets */

switch (proto) {
case (PPP_ADDRESS << 8 | PPP_CONTROL): /* looks like a PPP frame */
if (length < 4)
goto trunc;
proto = GET_BE_U_2(b + 2); /* load the PPP proto-id */
if ((proto & 0xff00) == 0x7e00)
ND_PRINT("(protocol 0x%04x invalid)", proto);
else
handle_ppp(ndo, proto, b + 4, length - 4);
break;
default: /* last guess - proto must be a PPP proto-id */
if ((proto & 0xff00) == 0x7e00)
ND_PRINT("(protocol 0x%04x invalid)", proto);
else
handle_ppp(ndo, proto, b + 2, length - 2);
break;
}

cleanup:
nd_pop_packet_info(ndo);
return;

trunc:
nd_pop_packet_info(ndo);
nd_print_trunc(ndo);
}

/* PPP */
static void
handle_ppp(netdissect_options *ndo,
u_int proto, const u_char *p, u_int length)
{
if ((proto & 0xff00) == 0x7e00) { /* is this an escape code ? */
ppp_hdlc(ndo, p - 1, length);
return;
}

switch (proto) {
case PPP_LCP: /* fall through */
case PPP_IPCP:
case PPP_OSICP:
case PPP_MPLSCP:
case PPP_IPV6CP:
case PPP_CCP:
case PPP_BACP:
handle_ctrl_proto(ndo, proto, p, length);
break;
case PPP_ML:
handle_mlppp(ndo, p, length);
break;
case PPP_CHAP:
handle_chap(ndo, p, length);
break;
case PPP_PAP:
handle_pap(ndo, p, length);
break;
case PPP_BAP: /* XXX: not yet completed */
handle_bap(ndo, p, length);
break;
case ETHERTYPE_IP: /*XXX*/
case PPP_VJNC:
case PPP_IP:
ip_print(ndo, p, length);
break;
case ETHERTYPE_IPV6: /*XXX*/
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case ETHERTYPE_IPX: /*XXX*/
case PPP_IPX:
ipx_print(ndo, p, length);
break;
case PPP_OSI:
isoclns_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
case PPP_COMP:
ND_PRINT("compressed PPP data");
break;
default:
ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));
print_unknown_data(ndo, p, "\n\t", length);
break;
}
}

/* Standard PPP printer */
u_int
ppp_print(netdissect_options *ndo,
const u_char *p, u_int length)
{
u_int proto,ppp_header;
u_int olen = length; /* _o_riginal length */
u_int hdr_len = 0;

ndo->ndo_protocol = "ppp";
/*
* Here, we assume that p points to the Address and Control
* field (if they present).
*/
if (length < 2)
goto trunc;
ppp_header = GET_BE_U_2(p);

switch(ppp_header) {
case (PPP_PPPD_IN << 8 | PPP_CONTROL):
if (ndo->ndo_eflag) ND_PRINT("In ");
p += 2;
length -= 2;
hdr_len += 2;
break;
case (PPP_PPPD_OUT << 8 | PPP_CONTROL):
if (ndo->ndo_eflag) ND_PRINT("Out ");
p += 2;
length -= 2;
hdr_len += 2;
break;
case (PPP_ADDRESS << 8 | PPP_CONTROL):
p += 2; /* ACFC not used */
length -= 2;
hdr_len += 2;
break;

default:
break;
}

if (length < 2)
goto trunc;
if (GET_U_1(p) % 2) {
proto = GET_U_1(p); /* PFC is used */
p++;
length--;
hdr_len++;
} else {
proto = GET_BE_U_2(p);
p += 2;
length -= 2;
hdr_len += 2;
}

if (ndo->ndo_eflag) {
const char *typestr;
typestr = tok2str(ppptype2str, "unknown", proto);
ND_PRINT("%s (0x%04x), length %u",
typestr,
proto,
olen);
if (*typestr == 'u') /* "unknown" */
return hdr_len;

ND_PRINT(": ");
}

handle_ppp(ndo, proto, p, length);
return (hdr_len);
trunc:
nd_print_trunc(ndo);
return (0);
}

/* PPP I/F printer */
void
ppp_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, const u_char *p)
{
u_int length = h->len;
u_int caplen = h->caplen;

ndo->ndo_protocol = "ppp";
if (caplen < PPP_HDRLEN) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}
ndo->ndo_ll_hdr_len += PPP_HDRLEN;

#if 0
/*
* XXX: seems to assume that there are 2 octets prepended to an
* actual PPP frame. The 1st octet looks like Input/Output flag
* while 2nd octet is unknown, at least to me
* ([email protected]).
*
* That was what the original tcpdump code did.
*
* FreeBSD's "if_ppp.c" *does* set the first octet to 1 for outbound
* packets and 0 for inbound packets - but only if the
* protocol field has the 0x8000 bit set (i.e., it's a network
* control protocol); it does so before running the packet through
* "bpf_filter" to see if it should be discarded, and to see
* if we should update the time we sent the most recent packet...
*
* ...but it puts the original address field back after doing
* so.
*
* NetBSD's "if_ppp.c" doesn't set the first octet in that fashion.
*
* I don't know if any PPP implementation handed up to a BPF
* device packets with the first octet being 1 for outbound and
* 0 for inbound packets, so I ([email protected]) don't know
* whether that ever needs to be checked or not.
*
* Note that NetBSD has a DLT_PPP_SERIAL, which it uses for PPP,
* and its tcpdump appears to assume that the frame always
* begins with an address field and a control field, and that
* the address field might be 0x0f or 0x8f, for Cisco
* point-to-point with HDLC framing as per section 4.3.1 of RFC
* 1547, as well as 0xff, for PPP in HDLC-like framing as per
* RFC 1662.
*
* (Is the Cisco framing in question what DLT_C_HDLC, in
* BSD/OS, is?)
*/
if (ndo->ndo_eflag)
ND_PRINT("%c %4d %02x ", GET_U_1(p) ? 'O' : 'I',
length, GET_U_1(p + 1));
#endif

ppp_print(ndo, p, length);
}

/*
* PPP I/F printer to use if we know that RFC 1662-style PPP in HDLC-like
* framing, or Cisco PPP with HDLC framing as per section 4.3.1 of RFC 1547,
* is being used (i.e., we don't check for PPP_ADDRESS and PPP_CONTROL,
* discard them *if* those are the first two octets, and parse the remaining
* packet as a PPP packet, as "ppp_print()" does).
*
* This handles, for example, DLT_PPP_SERIAL in NetBSD.
*/
void
ppp_hdlc_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h, const u_char *p)
{
u_int length = h->len;
u_int caplen = h->caplen;
u_int proto;
u_int hdrlen = 0;

ndo->ndo_protocol = "ppp_hdlc";
if (caplen < 2) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}

switch (GET_U_1(p)) {

case PPP_ADDRESS:
if (caplen < 4) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}

if (ndo->ndo_eflag)
ND_PRINT("%02x %02x %u ", GET_U_1(p),
GET_U_1(p + 1), length);
p += 2;
length -= 2;
hdrlen += 2;

proto = GET_BE_U_2(p);
p += 2;
length -= 2;
hdrlen += 2;
ND_PRINT("%s: ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", proto));

handle_ppp(ndo, proto, p, length);
break;

case CHDLC_UNICAST:
case CHDLC_BCAST:
chdlc_if_print(ndo, h, p);
return;

default:
if (caplen < 4) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}

if (ndo->ndo_eflag)
ND_PRINT("%02x %02x %u ", GET_U_1(p),
GET_U_1(p + 1), length);
p += 2;
hdrlen += 2;

/*
* XXX - NetBSD's "ppp_netbsd_serial_if_print()" treats
* the next two octets as an Ethernet type; does that
* ever happen?
*/
ND_PRINT("unknown addr %02x; ctrl %02x", GET_U_1(p),
GET_U_1(p + 1));
break;
}

ndo->ndo_ll_hdr_len += hdrlen;
}

#define PPP_BSDI_HDRLEN 24

/* BSD/OS specific PPP printer */
void
ppp_bsdos_if_print(netdissect_options *ndo,
const struct pcap_pkthdr *h _U_, const u_char *p _U_)
{
u_int hdrlength;
#ifdef __bsdi__
u_int length = h->len;
u_int caplen = h->caplen;
uint16_t ptype;
uint8_t llhl;
const u_char *q;
u_int i;

ndo->ndo_protocol = "ppp_bsdos";
if (caplen < PPP_BSDI_HDRLEN) {
nd_print_trunc(ndo);
ndo->ndo_ll_hdr_len += caplen;
return;
}

hdrlength = 0;

#if 0
if (GET_U_1(p) == PPP_ADDRESS &&
GET_U_1(p + 1) == PPP_CONTROL) {
if (ndo->ndo_eflag)
ND_PRINT("%02x %02x ", GET_U_1(p),
GET_U_1(p + 1));
p += 2;
hdrlength = 2;
}

if (ndo->ndo_eflag)
ND_PRINT("%u ", length);
/* Retrieve the protocol type */
if (GET_U_1(p) & 01) {
/* Compressed protocol field */
ptype = GET_U_1(p);
if (ndo->ndo_eflag)
ND_PRINT("%02x ", ptype);
p++;
hdrlength += 1;
} else {
/* Un-compressed protocol field */
ptype = GET_BE_U_2(p);
if (ndo->ndo_eflag)
ND_PRINT("%04x ", ptype);
p += 2;
hdrlength += 2;
}
#else
ptype = 0; /*XXX*/
if (ndo->ndo_eflag)
ND_PRINT("%c ", GET_U_1(p + SLC_DIR) ? 'O' : 'I');
llhl = GET_U_1(p + SLC_LLHL);
if (llhl) {
/* link level header */
struct ppp_header *ph;

q = p + SLC_BPFHDRLEN;
ph = (struct ppp_header *)q;
if (ph->phdr_addr == PPP_ADDRESS
&& ph->phdr_ctl == PPP_CONTROL) {
if (ndo->ndo_eflag)
ND_PRINT("%02x %02x ", GET_U_1(q),
GET_U_1(q + 1));
ptype = GET_BE_U_2(&ph->phdr_type);
if (ndo->ndo_eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
ND_PRINT("%s ", tok2str(ppptype2str,
"proto-#%u", ptype));
}
} else {
if (ndo->ndo_eflag) {
ND_PRINT("LLH=[");
for (i = 0; i < llhl; i++)
ND_PRINT("%02x", GET_U_1(q + i));
ND_PRINT("] ");
}
}
}
if (ndo->ndo_eflag)
ND_PRINT("%u ", length);
if (GET_U_1(p + SLC_CHL)) {
q = p + SLC_BPFHDRLEN + llhl;

switch (ptype) {
case PPP_VJC:
ptype = vjc_print(ndo, q, ptype);
hdrlength = PPP_BSDI_HDRLEN;
p += hdrlength;
switch (ptype) {
case PPP_IP:
ip_print(ndo, p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
}
goto printx;
case PPP_VJNC:
ptype = vjc_print(ndo, q, ptype);
hdrlength = PPP_BSDI_HDRLEN;
p += hdrlength;
switch (ptype) {
case PPP_IP:
ip_print(ndo, p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
}
goto printx;
default:
if (ndo->ndo_eflag) {
ND_PRINT("CH=[");
for (i = 0; i < llhl; i++)
ND_PRINT("%02x",
GET_U_1(q + i));
ND_PRINT("] ");
}
break;
}
}

hdrlength = PPP_BSDI_HDRLEN;
#endif

length -= hdrlength;
p += hdrlength;

switch (ptype) {
case PPP_IP:
ip_print(p, length);
break;
case PPP_IPV6:
ip6_print(ndo, p, length);
break;
case PPP_MPLS_UCAST:
case PPP_MPLS_MCAST:
mpls_print(ndo, p, length);
break;
default:
ND_PRINT("%s ", tok2str(ppptype2str, "unknown PPP protocol (0x%04x)", ptype));
}

printx:
#else /* __bsdi */
hdrlength = 0;
#endif /* __bsdi__ */
ndo->ndo_ll_hdr_len += hdrlength;
}